Self-lubricating and coloring projectile



Patented Apr. 23, 1946 sELF-LnealoA'rlNG VfooLoRINe 'ritoJECrrILn `loseph Schreib, Baltimore, Md. Application .time 5, 1943, ,serial No. '489,143

(o1. '1oz-"93) 2 Claims.

This invention refers to ammunition and more particularly to the construction of projectiles used in cannons, guns or rifles. It has among its objects .to provide a projectile that is self-lubricating; that will automatically lubricate the barrel ,of the gun it is fired from; and which will have an `arrangement for identifying itself by .distinctively marking the target it is used against. A further object is .to provide the projectile with .a novel type `of rifling band designed to provide-lubricant vand feed it through spaces provided in same in .such va manner vas to improve the cutting of the thread on the band as it passes through the rifling. Also to have this rifling band furnish the means for identifying the ammunition it is used with.

Other objects will become apparent as the invention is more fully set forth.

While various arrangements have been provided for lubricating the barrel of a gun used for firing projectiles, such have been limited to superficial treatment of the surfaces frictionally and mechanically engaging with one another, and the employment of a lubricant external to the projectile. This is usually called a hot dip process or modifications thereof. 'I'his invention avoids this process. In this invention the structure for containing the lubricant is considered paramount, and this consists of specially formed rings made to contain the lubricant and exude it to the rifling ring where it Will lubricate the latter for riing action and antifriction results as it passes through the barrel under fire. The rings are preferably made with dove-tailed parts to engage and hold in grooves in the projectile, and the back portions of the rings formed to hold a suitable lubricant and a coloring indicator adapted to exude out of the rings as the propelling pressures force the projectile through the rie barrel of a gun. The purpose of the coloring indicator is to provide a definite method of identifying a projectile or the gun it is used with, This is particularly valuable in keeping track of results, which is not practical in other forms of ammunition.

In the drawing, which illustrates an example of a projectile embodying this invention:

Figure 1 is a side elevation partly in section, of a projectile upon which are mounted riing bands embodying this invention;

Figure 2 is an end elevation of Figure 1; and

Figure 3 is an enlarged sectional View of the riing band and projectile shown in Figure 1.

Similar reference characters refer to similar parts throughout the drawing.

in .the grooves `3. .The espaces 6 between the sections are very minute and serve to permit `:very limited .amount of lubricant l to lpasslout between them. -lngaddition-the sections :have holes 4.or

passages 8 .through fthem for the Aradial :expulsion of the lubricant therethrough. The bottom portion and surfaces 9 of the rings 5 are enlarged to lit snugly in the dovetailed portions 3 of the grooves 2. A series of lubricant reservoirs I0 are formed in the bottom and open out internally against the bottom surface 4 of the grooves 3 and through passages 8. The passages I8 are arranged to contain coloring indicator Il and to flow out radially away from the projectile external surface. The passages are blanked off at 20.

The operation of firing the projectile from the barrel of a gun is as follows: The explosive charge presses against the back surface l2 of the bullet and forces it forward. This presses the first ring 5 into contact with the riling groove of the barrel, The ring on the projectile is relatively soft and moves forward therewith through the riing groove and takes on a helical formation conforming with the pitch of the riing. The ring and projectile rotate together in the riiling as they are forced forward through the barrel. Later the second ring comes into contact with the rifling groove and is cut likewise. The second ring accumulatively cooperates with the function of the rst ring and rifling groove and gives the projectile a continued and more forceful rotation. As the riling ring 5 is forced through the barrel, its convexedly curved external surface I3 is pressed inwardly by the surface of the barrel and the high pressure of the explosive gases therein. This presses on the body of the ring and makes it exude some of its lubricant against the back 4 of the groove, and thence through the passages 8 and spaces 6 to the surface of the ring and the rifling groove. This lubricates the surfaces and reduces the frictional resistance of the projectile and enables the riing groove to cut a surface riliing screw thread thereon, more readily.

When the projectile has passed out of the gun and reached its target, it tears a hole in same and in doing so acts on the expanded coloring indicator to shake and force it out externally from the ring, to color the target.

The type of lubricant usable in this invention is subject to variations and improvements as time passes and is therefore not accentuated as a part of this application, since specific protection is not sought in that regard. However, the type of lubricant considered suitable is that of a graphite base carried in a vehicle that leaves no residue or ash after discharge of the projectile, such as those of an alcohol nature. The colored indicator is preferably of an earthy nature carried in a high temperature greasy vehicle. The color of the indicator can be varied to suit the ammunition used and to identify where it has struck. The same cloor is preferably painted on the nose I6 of the projectile to identify the indicator used with it.

While but `one general form of the invention i is shown in the drawing and described in the speciiications, it is not desired to limit this application forrpatent to this particular form or in any other Way otherwise than limited by the scope thereof as it is appreciated that other forms of construction could be made that would use the same principles and come Within the scope of the appended claims.

Having thus described the invention, what is claimed is:

1. A projectile of the class described comprising in combination, a projectile body of conventional form and I material having dovetailed grooves formed concentrically about the axis thereof in the peripheral portion, a ring of metal adapted to conform with the riing of a gun in which it is fired and projected above the peripheral surface of the said body to adapt itself thereto, said ring being of conventional material suitable for the purpose and having its inner portion formed into a dovetail contour with the said grooves in the body, said ring having minute interstices and spaces formed therein with lubricant forced therein adapted to exude therefrom when used in the rifiing of a gun during its travel therethrough and passages in said ring for holding coloring matter for marking the target.

2. A projectile of the class described comprising in combination, a projectile body of conventional form and material having dovetailed grooves formed concentrically about the axis thereof in the peripheral portion, a ring of metal adapted to conform with the rifling of a gun in which it is fired and projected above the peripheral surface of the said body to adapt itself thereto, said ring being of conventional material suitable for the purpose and having its inner portion formed into a dovetail contour to conform with the said grooves in the body, said ring having minute interstices and spaces formed therein with lubricant forced therein adapted to eXude therefrom when used in the riiiing of a gun during its travel therethrough and passages in said ring for holding coloring matter for marking the target, and tapered portions in said interstices in the inner portion thereof for forming a reservoir for the lubricant to accumulate.

JOSEPH SCHREIB. 

